The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. The process of tracking items requires that each item have its own readable information. Conventionally, each item is marked locally with a visible serial number, which is printed on a label, or is used with a bar code having a machine-readable serial number. Such serial numbers may be correctly read when the items are located so that the serial numbers on the items can be visually observed or be scanned by a bar code scanner. However, manual reading may introduce errors. Further, the items may be in a shield boundary (e.g., cabinet) and are not easily accessible from outside. In this case, it is necessary to open the boundary to read the serial number on each item.
Radio frequency identification (RFID) tags function as contactless markers. Each RFID tag has its own unique identification or identifier (ID). The IDs on the RFID tags are read by an RFID reader using RF signals, and can be used for inventory purpose. Items having the RFID tags can be tracked using the IDs of the tags. The RFID tags can be either active or passive RFID tags. An active RFID tag is used in a variety of applications since the active RFID tag has its own internal power source. However, the size and cost for the active RFID tag is high. In addition, when tracking items in the shield boundary, there is no way to know how many active RFID tags will answer to the RFID reader. Moreover, there may be a confusion between the items supposed to be read and the IDs obtained. The operator of the RFID reader may not know the items in the boundary. The operator may not know where the items are in the boundary.
Therefore, there exists a need for a method and system to improve the access to the item's ID. There is also a need for a method and system to improve the time to scan/read the ID among multiple IDs for inventory purpose.